API Tester

Generates and verifies API tests strictly from real OpenAPI specs, route code and existing tests, and only executes requests with explicit authorization.

Web & APIIntermediate★ 750⑂ 77AI score 7/10Last updated: Aug 10, 2026

What it does

Reads OpenAPI/Swagger files, routes, controllers, DTOs, validators and existing tests first to collect verifiable contract evidence.
Builds a contract matrix covering method/path, auth and permissions, request constraints, declared responses, side effects and idempotency, plus test environment and cleanup strategy.
Flags mismatches between spec, implementation and current tests, and asks for confirmation instead of freezing a guess into a new test.
Writes a minimal test suite in the project's existing framework, directory layout and assertion style — happy path, real boundary rules, declared permission rules and reachable error branches only.
Before execution it confirms base URL, environment type (local/test/staging/production) and whether write operations are allowed; afterwards it reports the exact command, exit status, data cleanup and separates pre-existing failures from new ones.

Who it's for

Backend developers adding integration or regression tests to an existing API.
Teams whose OpenAPI documents have drifted from the actual implementation.
Anyone burned by AI-invented status codes or response shapes that don't exist.
Teams that want a hard guardrail against accidental writes to production.

Examples

"Add integration tests for the /orders endpoint" — reads the spec and controller and only asserts the error codes the contract actually declares.
"Check whether this release breaks API compatibility" — diffs spec vs. implementation vs. client types and proposes regression cases for each mismatch.
"Run the tests you just wrote against my local environment" — confirms the environment and write permissions, runs the repo's own test script, and reports results plus cleanup status.

· · · Install guide · · ·

Try it now, no install

Paste this into Claude to use the skill without installing anything.

Read the instructions in this file and follow them to help me:
https://raw.githubusercontent.com/laolaoshiren/claude-code-skills-zh/HEAD/skills/api-tester/SKILL.md

What I want: (describe your task here)

If Claude can't open the link, open it yourself and paste the contents instead.

↓ If it works for you, download the ZIP below and install it. Then it runs on its own — no pasting each time.

Install in the Claude app (no terminal)

Download the ZIP with the button below.
In Claude, open Settings → Capabilities and turn on 'Code execution and file creation'. (one time)
Go to Customize → Skills → + → 'Upload a skill' and upload the ZIP.

↓ Download ZIP

Install in Claude Code

Let Claude do it — paste this into Claude Code

Install the skill I found on Claude Skill Mart.
Copy the skills/api-tester folder from the GitHub repo laolaoshiren/claude-code-skills-zh into my ~/.claude/skills/api-tester/.
When it's done, tell me in one line what this skill can do.

Install with a command instead

git clone https://github.com/laolaoshiren/claude-code-skills-zh.git /tmp/cc-skills-zh && mkdir -p ~/.claude/skills && cp -r /tmp/cc-skills-zh/skills/api-tester ~/.claude/skills/

⚠ This is a third-party skill. Check the source repository before installing.

Open your terminal.
Clone the repository: git clone https://github.com/laolaoshiren/claude-code-skills-zh.git
Create the skills folder if needed: mkdir -p ~/.claude/skills
Copy the skill: cp -r claude-code-skills-zh/skills/api-tester ~/.claude/skills/
Verify that ~/.claude/skills/api-tester/SKILL.md exists.
Restart Claude Code and try a prompt like "Write integration tests for this project's API".
If you want it to actually send requests, state the environment (local/test/staging) and whether write operations are permitted.

View source on GitHub ↗License: MIT